Offsetting – the practice of paying others to reduce their emissions for you – is the world's best first step in tackling collective inaction on climate change.

This view contradicts what is often expressed in these pages, most recently by my compatriot Naomi Klein in her criticisms of green groups. But it reflects one simple truth: the Earth's atmosphere is agnostic about who emits. So long as global emissions are capped at the level that science demands, their distribution is irrelevant.

Operational since 2001, it has registered more than 7,200 projects and issued credits corresponding to almost 1.4bn tonnes of emission reductions. It has channelled more than US$215bn in technology, knowledge, and finance to developing countries, virtually all from private sources at negligible taxpayer expense.

The CDM also provides an extensive library of technical tools for assessing appropriate emissions levels in well over 100 areas, including energy, industrial processes, and transportation. Emulated from California to China, these tools provide an essential basis for measuring, reporting, and verifying emissions data and have been universally praised.

For three reasons, the CDM is the ideal bridge to the world that we all want.

First, it gets the ball rolling by providing quick wins. Offsetting lets emitters sponsor emission reductions wherever they are cheapest and easiest to achieve. The cost of reducing emissions varies significantly across countries and sectors, and the CDM has the world's broadest geographic and sectoral reach. As such, the CDM allows for an identical quantity of reductions to be achieved at the lowest possible cost. In turn, these savings can be – and have been – spent on adopting tougher emission targets.

Second, mechanisms like the CDM build domestic constituencies supportive of ever stronger action on climate change. These include those you would expect, such as environmentalists and vendors of clean technology, but also those who otherwise have no skin in the game, such as investors, financial institutions, and companies motivated by corporate social responsibility. And supportive constituencies matter if you want to do more ambitious things, given that warnings about long-term climate impacts are beyond many politicians' time horizons and pale next to the desire for economic growth.

Third, the CDM has acquainted emitters around the world with the practice of reducing emissions. A point underappreciated by Klein and others is that countries are sovereign: they face no legal imperative to reduce their emissions and, to the contrary, face intense political pressure to emit as much as they can. Offsetting normalises the practice of reducing emissions, such that all major emitters now speak openly of limiting their emissions and implementing policies and measures to do so. Would they – or more accurately, could they – have done so absent their experiences with mechanisms like the CDM?

None of this means that the CDM is perfect. It needs to move beyond the one-to-one ratio between reducing emissions in one location and increasing emissions in another location. Although it already employs various means to do precisely this – and has most likely delivered a net benefit to the atmosphere – further steps are needed. These largely involve more conservative assumptions about emissions at every stage of the process and are being actively explored.

The CDM also needs to address the criticism that a small number of projects have had damaging non-climate impacts, such as dams flooding villages or covered landfill sites putting waste-pickers out of a job. The United Nations is on public record as supporting greater transparency in assessing the impacts of CDM projects, and it is committed to addressing and resolving any allegations of negative impacts. Equally, the undisputed benefits of the vast majority of CDM projects should not go neglected, among them reduced local air pollution, better human health outcomes, and increased employment.

More broadly, offsetting needs a world with strong emissions targets set at the level necessary to give the world a fighting chance at avoiding runaway global warming. This will require a significant increase in ambition, requiring major shifts in patterns of production and consumption, particularly in developed countries.

Offsetting bridges the gap between the way things are and the way things should be. It does not "solve" climate change any more than food banks solve hunger or shelters solve homelessness. But it is an essential first step, creating a platform of stability on which more ambitious policies can be built. Efforts to improve it and increase its use should be strengthened, not shunned, as the world moves toward a global climate agreement by its self-imposed 2015 deadline.

• Robin Rix is the lead officer for carbon markets strategy at the United Nations climate change secretariat

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